The light from each star is directed through a prism to produce a spectrum. Each of the spectra has a set of absorption lines created by the presence of hydrogen in the stars' atmospheres.

White light is made of a spectrum of different colours. Light can be split up into these separate colours using a prism. There are three primary colours of light, which can be combined to make ...

It is important to point out that we are not so much interested in dispersive prisms that split a beam of white light into its spectrum of colors, although they make great album covers.

A spectrometer is a pretty common lab instrument, useful for determining the absorbance of a sample across a spectrum of ...